According to the Arrhenius equation, k=Ae−RTEa.
The given equation is k=(5.5×1011 s−1)e−T28000.
Comparing the exponent of e in both equations:
RTEa=T28000
Ea=28000×R
Substituting the value of R=8.3 J K−1 mol−1:
Ea=28000×8.3 J mol−1
Ea=232400 J mol−1
Ea=232.4 kJ mol−1
Rounding to the nearest integer, the activation energy is 232.
Answer: 232